So now we're in the fourth layer of the U.S. reference model, the transport layer, welcome to the
layer of TCP.
The transport layer is the level at which system reliability and quality are ensured.
The basic function of the transport layer is to accept data from the layer above.
Split it up into smaller units.
Past these data units to the network layer.
And ensure that all the pieces arrive correctly at the other end.
OK, so now let's look at the functions of the transport layer in detail.
Service point addressing.
Transport layer header includes service point address, which is the port address, this layer gets
the message to the correct process on the computer, unlike network layer, which gets each packet to
the correct computer.
Segmentation and reassembling.
A message is divided into segments.
Now, each segment contains a sequence number which enables this layer to reassemble the message.
The message is reassembled correctly upon arrival at the destination and replaces packet's which were
lost in transmission.
Connection, control.
It includes two types, Conexion, less transport layer, each segment is considered as an independent
packet and delivered to the transport layer at the destination machine.
Connection oriented transport layer.
Before delivering packets, connection is made with the transport layer at the destination machine.
Flow control.
And this layer flow control is performed and duen.
The rate of data transmission between two nodes must sometimes be managed to prevent a fast sender from
transmitting more data than can be supported by the receiving data buffer causing a buffer overrun.
And we don't want that.
Air control, air control is performed end to end in this layer to ensure that the complete message
arrives at the receiving transport layer without any air.
Error correction is done through retransmission.
On the Internet, TCP and UDP provide the services for most applications.
Coming up next, we'll look at all the other details of the transport layer under TCP and UDP topics.